After the Michigan hockey team’s 5-1 loss Tuesday to Bowling Green, Michigan coach Red Berenson was asked about his team’s defensive struggles. Like he has all season, he mentioned poor defensive-zone coverage.

Defensive-zone miscues have been an alarming trend for the Wolverines and have led to many easy goals in front of the net for opponents. This came as a surprise to those who pegged Michigan as having one of the best defensive units in the country before the season began.

The unit was expected to be led by junior defenseman Jon Merrill — a 2010 second-round draft pick of the New Jersey Devils and a preseason all-CCHA selection. But when Merrill suffered a cracked vertebrae on Oct. 9, the defense took a turn for the worse.

This season, the Wolverines have struggled mightily to keep the puck out of their own net — their average of 3.40 goals allowed per game is currently last in the conference. The absence of Merrill didn’t help, but there are bigger issues than one missing player. Whether it is the defensemen or the forwards, the defensive effort hasn’t been what it needs to be for Michigan.

Merrill finally started on Tuesday night when the Wolverines squared off against Bowling Green, but his presence didn’t have the expected cataclysmic effect. Paired with freshman Jacob Trouba, who helped the U.S. junior team capture a gold medal in Russia less than a week ago, the two players controlled the game while on the ice.

“I think anytime you can play with a player like Jacob Trouba, it’s a real honor,” Merril said. “He’s a great player and makes it easy for me out there. It was just our first game together, but hopefully we can start meshing well.”

The defensive effort as a whole, though, was not up to par.

Injuries have been a constant thorn in the side for the defense this season. Just when the unit appeared to be coming together and fully healthy, sophomore Brennan Serville and junior Mac Bennett were injured during Tuesday’s game. Berenson said that Serville is day-to-day and Bennett is out for at least a “couple of weeks.” Along with those two players, junior Kevin Clare — still on the injury list — will also not play this weekend.

“We were excited to get Jonny Merrill back and then Mac Bennett goes down,” Berenson said. “Mac’s been arguably in our top pair all season.”

With the depleted defensive corps, Berenson will use senior forward Jeff Rohrkemper as a defenseman this weekend against Alaska. Rohrkemper, who saw time at the position against Northern Michigan earlier in the season, does not have much experience at the position.

“I think when (Rohrkemper) realizes how bad this team needs him, and how bad we need to play better defense, hopefully he’ll be fine,” Berenson said. “He’s got good defensive instincts. He’s a team player and he’s a senior.”

Berenson also noted the play of the forwards on the defensive end — and the correlation between their ability to control the puck and maintain possession — and the defensive flow. Against Bowling Green, the puck was constantly deep in the Wolverines zone, and the offense failed to get any momentum going.

The miscues, which resulted in at least two easy Bowling Green goals oTuesday, have stemmed from a combination of miscommunication and lack of awareness. With a depleted defensive corps, it will be even more important for the defensemen to communicate and understand exactly what their role is. Berenson said that he has been looking at the forwards’ play on defense just as much as their offensive production.

“We’ve got to be a lot more defensively aware,” he said. “When you look at the score sheet and you see someone who’s minus four, he’s not had a good game. Luke Moffatt scored his first goal of the year, but he may have taken himself out of the lineup just the way he played defensively. You got to play hard in the defensive zone. None of us are good enough to outscore our mistakes.”